Serum or plasma cyanide mass concentration (total)
This test measures the amount of cyanide in your blood or plasma, which is a toxic substance that can affect your body’s ability to use oxygen.
["Cyanide levels help assess exposure to toxins or metabolic conditions that may produce cyanide as a byproduct."]
Key facts at a glance
- LOINC
- 4534-4
- Short code
- CyanmetHgb MFr Bld
- Synonyms
- CyanmetHgb MFr Bld
- Category
- hematology
- Sample
- whole-blood
- Container
- Lavender-top (EDTA)
- Units
- N/A
- Ref low
- 12
- Ref high
- 17.5
- Critical range
- 7 N/A – 20 N/A
- Fasting
- false
- Population
- adult
- Sex
- all
- Age range
- 18–65 years
- CPT
- 85018
- SNOMED
- 900000000000003004
- Specimen volume
- 3 mL
- Stability
- Room temperature: 4h, Refrigerated: 24h
- Hemolysis max
- 0
- Lipemia max
- 0
- Icterus max
- 0
- TAT
- 4–24 hours
- Order
- routine
Why This Test Might Be Ordered
Your healthcare provider may order this test if you’ve been exposed to cyanide (e.g., from industrial accidents, certain medications, or poisoning). It may also be checked in cases of metabolic disorders, such as certain inherited enzyme deficiencies, or if you have symptoms like weakness, shortness of breath, or confusion that could suggest cyanide toxicity.
What to Expect Before the Test
No special preparation is usually needed. You may have a blood draw from a vein in your arm. If you’re taking medications that could affect cyanide levels, let your provider know.
What the Results Mean
Results are interpreted based on your symptoms, medical history, and exposure circumstances. High levels may indicate recent poisoning or metabolic issues, while low levels may not be clinically significant unless part of a broader evaluation.
Common Causes of Abnormal Results
Elevated levels can occur from cyanide poisoning (e.g., from industrial or household chemicals), certain medications, or rare genetic disorders. Low levels are less common but may be seen in healthy individuals without exposure.
Reference range
Adult males: 13.5-17.5 g/dL; Females: 12.0-16.0 g/dLN/A
No special preparation usually required. Stay well hydrated. Inform your healthcare provider of all medications and supplements you are taking.
Clinical interpretation
How abnormal results are interpreted and what conditions they suggest.
Clinical Significance
Short name
Total cyanide levels
Frequently asked questions
What symptoms might I experience if my cyanide levels are abnormal?
How often should I get this test?
Can diet or lifestyle affect this test?
Sources
- 1
- 2Lab Tests OnlineSource
- 3
Click any link to access the full source. PubMed Central (PMC) links provide free full-text access.
This information is for educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment.
This content is for general informational and educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment. Always seek the guidance of a qualified healthcare provider with any questions you have about a medical condition, and never disregard professional medical advice or delay seeking it because of something you read here.
If you think you may have a medical emergency, call your local emergency number or go to the nearest emergency department immediately.
Medically reviewed by WellAlly Editorial Team Last reviewed August 16, 2026. · Read our editorial policy